Electric elevator



I Aug. 3,1926.

P. H.. BRODESSER ELECTRIC ELEVATOR Filed June 2, 1922 3 Sheets-Sheet 1 A TTORNEY3.

P. H. BRODE SSER ELBCTRI C ELEVATOR Filed June 2, 1922 3 Sheets-Sheet 2 Aug. 3 1926.

P. H. BRODESSER ELECTRI C ELEVATOR Filed June 2, 1922 3 Sheets-Sheet 5 INVENTOR.

V Xfl 1 5 M FZ/MM/ .l TTORNEYJ.

Patented Aug. 3, 1926.

UNITED STATES PETER H. BRODESSER, OF MILWAUKEE, WISCONSIN.

ELECTRIC ELEVATOR.

Application filed June 2,

This invention relates to elevators and is particularly directed to a system of control for electric elevators.

Objects of this invention are to provide a system for controlling elevators by which the elevator may be accurately stopped in correct alignment at the desired floor; to provide such a system in which the elevator is slowed down as it approaches the floor and is automatically stopped at the exact floor level; and to provide such a system in which manual and automatic control-of the elevator are combined to secure the above enumerated results.

Further objects are to provide a system of control for electric elevators in which a small motor and a large -In0tor are provided, which are respectively connected with a winding drum by a large and relatively smaller reduction gearing; in whichthe smaller motor is used through its large reduction gearing to slowly start the load and give it a certain predetermined speed, and thereafter to allow the larger motor to take the load and further accelerate it; and to provide such a system in which the use of standard equipment in its major part is permitted.

Further objects are to provide a system for the control of electric elevators in which a relatively small starting current is used, thereby avoiding the overloading of the motors on the one hand and the excessive line current at starting on the other; to provide such a system in which the usual large losses in the control resistances are avoided, and in which each of the motors is kept, during a largepart of the time, working at its most eflicient speed.

Further objects are to provide a system for automatically aligning the car with the particular floor at which it is desired. to stop; to secure such automatic alignment independently of any stretch or elongation that may occur in the cables associated with the counterweight.

Further objects are to provide a system of two-motor elevator operation for securing accurate alignment of the elevator with the floor, in which a stationary brake is employed. that is to say, an electromagnetic brake which is not called upon to rotate but which is at all times relatively stationary to thereby secure all of the protection afiorded' by stationary b akes while allow- 1922. Serial No. 565,416.

ing the accurate and flexible control necessary for the proper alignment of the elevator with the floor.

Further objects are to provide a system in which the brake is so associated with the two motors that it is released when either motor operates; in which automatic electromagnetic means are provided for shifting the load from one motor'to the other; in which the auxiliary motor, together with its drive and the brake, jointly and independently, sustain the load when such load is at rest.

Further objects are to provide a multiple speed control for alternating current systems for electric elevator drive; in which the speed control of the alternating current motors is so secured that the usual type of alternating current motor may be employed; and to provide such a system, in which, although alternating current motors of the usual construction are utilized, it is still possible to secure accurate speed control and accurate floor alignment.

Embodiments of the invention are shown in the accompanying drawings, in which:

Fig. 1 is a diagrammatic view showing a system for electric elevator control in which alternating current motors are employed.

Fig. 2 is a similar system in which direct current motors are employed.

Fig. 3 is an elevation, partly in section, of the motors with the automatic devices associated therewith. showing a convenient association of such devices.

Fig. 4 is a plan view of the structure shown in Fig. 3.

Fig. 5 is a fragmentary elevation of a portion of the apparatus for automatically aligning the elevator at the particular floor at which it is desired to stop.

Fig. 1, showing one form of the invention, will first be described. In this figure, a system for controlling electric elevators .is disclosed in which a relatively large main motor indicated generally at 1 and a relatively small or auxiliary motor indicated generally at 2 are provided. The large mo tor has its armature 3 directly and permanently connected to a shaft 4 which, by means of the worm 5 and worm wheel 6, drives the winding drum 7. The auxiliary motor has the armature 8 connected by means of a Worm 9 with a worm wheel 10 loosely mounted upon the shaft 4. A friction clutch 11 is adapted to couple this loosely mounted worm operatively to the shaft 4, under certain predetermined conditions, as follows: either when the auxiliary motor is driving, or when the entire system is still, that is to say, when there is no current flowing in the circuits. The clutch is released by means of an electromagnetic device, comprising a solenoid 12, a plunger 13, and lever 14, whenever current flows in the stator windings of the main motor 1. A stationary brake, indicated generally at 15, is provided upon the shaft 4, the disk 16 of which is permanent-ly connected to such shaft, the brake band 17 being forced apart by any suitable mechanism operated from the plunger 18 of the solenoid 19. The system is so designed that when current flows through the stator windings of either the auxiliary or main motor the brake will release.

manually operable controller is provided and is preferably located upon the elevator car in the usual manner. It comprises a lever 20 pivoted at 21 and provided with an operating handle 22. Upon the upper side of the lever, a plurality of contacts 23, 24 and 25 are provided and are connected by means of the conductors 26, 27 and 28 with the mains 29, 30 and 31. The stationary contacts of the controller cooperating with the movable contacts just described comprise four series ofcontacts, ne set 32, 33 and 34 being connected with the stator windings of the auxiliary motor by means of conductors 35, 36 and 37. It is to be noted, however, that the conductor 35 does r ot lead directly to one of the taps of the stator winding of the auxiliary motor, but by means of the conductor 38 leads through the solenoid 19' of the electromagnetic brake and from thence by means of conductor 39 to the appropriate tap on the stator winding of the auxiliary motor. similar series of contacts is provided upon the opposite side of the controller with, however, the single exception that two of the taps leading to the stator winding are reversed so as to give a reverse direction of rotation of the polyphase auxiliary motor, it, of course, being understood that the mains 29, 30 and 31 supply three-phase current to the system.

The next series of contacts 40,41 and 42 lead by means of conductors 43, 44 and 45 to the stator windings of the main motor. However, the conductor 44 does not lead directly to the stator windings of the main motor, but leads to the solenoid 46 of an electromagnetic 'contactor and from thence by means of the conductor 47 to its appro- DrIate tap on the main motor stator winding. In a similar manner, the conductor 43 leads through the'solenoid 19 of the electromagnetic brake, and from thence by means of the conductor 48 to its appropriate tap on the stator winding of the main motor. The corresponding set of contacts upon the opposite side of the controller are connected in the same manner except that two of the taps of the stator windings are reversed so as to give a reverse direction of rotation of the main motor.

Fron the construction thus far given, it will be seen that when the auxiliary motor is energized, the solenoid 19 of the electromagnetic brake is energized and the brake is released. It will also be seen that when the main motor is energized both the electromagnetic brake solenoid 19 and the contactor solenoid 46 are energized.

The contactor comprises the solenoid 46, previously described, a plunger 49, and movable contact 50. This movable contact is carried by the plunger and insulated therefrom, and is adapted to connect the two stationary contacts 51 and 52, thereby closing an auxiliary circuit from the mains 30 and 31 through the solenoid 12 of the electromagnetic friction brake, through the medium of the conductors 53 and 54.

Upon the lower end of the controller lever 20, a plurality of contacts 55, 56 and 57 are provided, and are connected with the mains 29, 30 and 31, respectively. It is to be noted, however, that these contacts are not connected directly to the mains, but through the medium of switch blades 58. These switch blades form a part of an automatic cutout device, and one connected together by means of an operating plunger 59 which extends outwardly from a housing 60, see Fig. 5, and is operated by a lever 61. This lever 61 is pivoted at 62 and is pressed outwardly by means of a spring 63. At its free end,

it carries a roller 64 which is adapted to be actuated by means of a cam 65 secured to some portion of the hatchway, or runway, of the counterweight 66. It is to be noted that this cam has a gradual approach on each side and a central peak 67. When the roller 64 arrives. at the central peak 67, the switches 58 are opened and the auxiliary circuit controlled thereby is correspondingly opened.

The stationary contacts corresponding to the last described movable contacts are indicated at 68, 69 and 70 and are connected t the conductors 35, 37 and 36 respectively. It will be seen, therefore, that when the controller is moved to the first point to the right that the auxiliary circuit established by the contacts 55, 56 and 57 and the cooperating contacts 68, 69 and 70 is identical to that established by the stationary contacts 32. 33 and 34 and the correspond ingmovable contacts when the controller is moved to its second position to the right.

However, this auxiliary circuit includes the automatic switches and, it will be seen, is

open when the car exactly aligns with a to the second point, the main motor is then energized and the auxiliary motor deenergized. The main motor having been rought. up to a certain speedtimmediate- 1y picks up and assumes the load without any excessive line current, or loading, resulting. It is to be noted that when either motor is energized, the brake is released and when the main motor is energized, the contactor blade 50 completes'the auxiliary circult through the electromagnetic control of the friction clutch, thereby opening such zlutch and mechanically disconnecting the auxiliary motor from the hoisting mechani sm. l

' When it is desired to stop at a give floor, the controller is moved to the first position. In this position, the auxiliary circuit of the auxiliary motor is established .and such motor drives the car at a reduced rate of speed towards the floor landing. At the time the car exactl aligns with the floor, the automatic switches function and cut out the auxiliary motor as previously described.

Fig. 2 shows a further modified form of the invention and, shows asystem adapted for direct current. The same arra ement of hoistin mechanism, 'brake, iction clutch, an contactor is employed in this system as in that previously described. The main motor armature .is indicated at 71 and its field at 72. The auxiliary motor armature is indicated at 73 and its field at 74. The contactor solenoid is indicated at .75. The same reference characters 50, 51 and 52 indicate the movable and stationary contacts of this contactor.

The controller lever 76 "is similarly pivoted .ad'acent its approximate central portion as indicated at 77 and isprovided with an operating handle 78. Its up er portion carries four movable contacts 79, 80, 81 and 82, the contacts and 82 being connected by means of conductors 83' with one of the mains 84. The up 'rmost contacts 79 is connected to one o the brushes 80 of the armature 71 of the main motor by means of the conductor 85. The contact 81 is connected by means of conductors 86 and 87 with one of the brushes" 88 of the auxiliary motor. The other brush 89 of the main motor is connected through the solenoid 75 of the contactor and through the solenoid 19 of the electromagnetic brake and to the main 90 by, means of conductors-91, 92 and 93. The second brush 94 of the auxiliary motor is similarly connected with the main 90 but its circuit does not pass through the contactor solenoid 75 but only through the brake solenoid 19. An auxiliary circuit for the solenoid 12-of the friction clutch is provided .by means of conductors 94 and 95 and isu'iontrolled by the contacts 50, 51 and 52 of the contactor in a manner similar to that previously described.

When the controller lever is moved to the second point to the right, it connects the brush 88 of the auxiliary motor to the elongated contact 96. From thence the circuit passes by meansof conductors 97 and 98 to one side of the field 74 of the auxiliary motor. The other side of the field is connected by means of conductors 99 and 100 to a contact 101 and from thence through a resistance 102 to the other second point position contact 103. This contact is connected, when thecontroller is in the position described, that is to say, second point right, with the main 84 by means of con' ductor 83. It will be seen, therefore, that the armature and field of. the auxiliary motor are connected in series with the resistance 102 and with the solenoid19 of the brake. The auxiliary motor, therefore, runs at a relatively low speed and slowly starts the car and hoisting mechanism and rotates the armature 71 of the main motor. When the controller is moved to the vnext point, the resistance 102 is cut-out and the auxilia motor runs at .itsfull speed. When t econtroller is movedito the next position to the right, the contact 79 engages the elongated contact 104 and connects the brush 80 of the main motor with its field 72 by means of conductors 105 and 106.. The other side of the field 72 is connected by means of conductors 107 and 108 to contact 109 through 'a resistance 110 to contact 111. From this point, the circuit continues through conductor 83 to the main" 84. The other brush 89 of the main motor is connected through the contactor solenoid 75 and the brake solenoid 19 with the main 90, as will be readily seen. It will be seen, therefore, that when the controller is in the last described position, the main motor is connected through the solenoids-ofthe contactor and brake and through the resistance 110 with the mains. The elevating mechanism and, car are consequently accelerated. It is to be noted, however, that the armature of the main motor was already rotated at a fair rate of speed before the main motor was energized, thereby cutting down the starting current as previously descri ed- It is also to be noted that the trio '1 is placed in series in this circuit.

tion brake is opened or released as its auxiliary circuit has been closed by the contactor.

l When the controller is moved to its last point to the right, all of the resistance is cut out of the main motor circuit and the elevator is driven at its maximum rate of speech The lower portion of the controller lever 76 carries a pair of movable contacts 112 and 113. lhese contacts are connected respectively with the brush 88 of the auxiliary motor through the medium of the conductor 87, and with the automatic cut out switch 11% through the medium of conductor 115. From the automatic switch, the last mentioned contact is connected with the main 8% by means of conductor 116. This switch is operated by means of the stem 59 in the same manner as the automatic switches previously described. When the controller is moved to first position to the right, the contact 112 cooperates with the contact 117 connects the brush 88 with one side of the field 7 1. LhG other side of the field is connected to contact 119 and from thence to the main 8 after passing through the automatic switch 11 1. The other portions of the auxiliary motor circuit are the same as that described for second and third point controller positions.

it will be seen, therefore, that when the controller is in its first position that the auxiliary motor is connected with the mains and a resistance and the automatic switch The auxiliary motor, therefore, slowly drives the car towards the desired landino'. l Vhen the car aligns with the landing, the automatic switch opens and the car is stopped exactly in its correct position.

In order to secure the reverse direction of rotation, the opposite side otthe controller is provided with corresponding contacts so connected with the fields of the motors that the current in such fields is reversed relatively to the armatures. A similar organization of contacts at the lower portion of the controller is provided so that the correct direction of rotation of the auxiliary motor, when under the control of the automatic switch, is assured.

1n the "form of the invention shown and described, it has been contemplated associatingan auxiliary member or cross head 120 with the counterweight 66 and suspending such cross head by means of a cable 121 so that the cross head position'is independent of the stretch of the main supporting cables 122 of the counterweight; The housing 60 for the automatic switches is carried by this cross head as shown in Fig. 5 so that stretching of the cables will not afiect the correct alignment of the car with the floor. However, it is to be understood that the auto matic switches may be carried directly by the car, if so desired, and that the cam may be positioned in the hatchway or, as an alternative construction, the cam may be carried by the car and automatic switches may beplaced in the hatchway.

It will be seen from the disclosure herewith given that a combined automatic and manual control for electric elevators has been provided in which the car maybe made to slowly approach the desired tloor and when arriving in exact alignment with such floor, to be automatically stopped. if it is desired to travel past this floor while on reduced speed, it is merely necessary to move the controller to its second point position. 111 this position, the automatic switches are bridged and the auxiliary motoncontinues to operate, although the automatic switches will open as the floor is passed.

It will further be seen that a system of control for electric elevators has been provided in which both of the two motors are so associated with the hoisting mechanism and electrical circuits, that either motor may continuously operate, if desired, at its most eiiicient speed. it will further be seen, that in the normal operation of the elevator, very little energy is wasted inthe resistance as a large part of the control is secured by changing motors.

1 claim:

1. In a control system for electric elevators, the combination of a hoisting apparatus, a main motor and an auxiliary mot-or, mechanism for connecting said motors to said hoisting apparatus, a manually operable controller for starting the elevator by said auxiliary motor and for thereafter accelerating said elevator by said main motor, an automatic device including switches actuated when the elevator arives at a floor landing to open such switches, and means carried by said controller for electrically connecting said auxiliary motor with said switches when said controller occupies a predetermined position, whereby said elevator may be run past any iioor landing when driven either by said main or auxiliary motor, or may be automatically stopped at said floor landing when driven by said auxiliary motor.

2. A system of control for electric elevators having a hoisting drum and a stationary brake, said system comprising a main motor directly mechanically connected to said hoisting drum, an auxiliary motor adapted for intermittent connection to said hoisting drum through a reduction gearing, electromagnetic means for operatively connectingsaid auxiliary motor and said hoisting drum under predetermined conditions, other electromagnetic means controlled by the current supplied said main motor to control the actuation of said first mentioned electromain motor or sai source of electric supply, and or connecting an automatic device for interrupting .magnetic means, a manually operable controller for selectivel connecting either said (i auxilia motor to a said auxiliar motor through a secondary circuit to sai source of electric supply, ang.

sai secondary circuit as the elevator arrives at each floor landing.

3. A system of control for electric elevators comprising a hoisting mechanism, a main and an auxiliary motor operatively connected thereto to drive the hoisting mechanism at difierent speeds, manual means for selectively connecting either of said motors to a source of electrical energy, a normally closed automatic switch controlling the circuit of the auxiliary motor, a movable switch actuating member associated with the travelling portions of the hoisting mechanism and adapted, when moved in one direction, to open said automatic switch, cooperating and relatively stationary members adaptedto engage and actuate said movable switch actuati member in said direction at predetermin efi ints in,its line of travel between its initiaFand final dpositions, said switch being normally close and adapted to be automatically opined by said relars, w e

tively stationary mem reby said mechanism may be automatically stopped at certain points in its line'of travel when nected to said hoisting mechanism,

propelled by the auxiliary motor. 4. A system" of control for electric ele-' vators compri a hoist' mechanismineluding a load lifting plat em, a series of landing stations, a main motor mechanically connected to "the hoisting mechanism, an auxiliary motor normally conf th ectromagnetic means or interru e operative connection between sais il il xiliary motor "and said hoiStingQmech'a'ni'sm, a contactor e'to energization of said main motor for controlling said electromagnetic means, manual means for se arately connecting either of said motors with a source of electrical energy, and automatic means normally operative whenever the hoisting platform reaches a landing station .a for disconnecting said auxiliary motor from said sourceof electrical energy, said motors being otherwise subject to separate manual control, p

5. A system of control for electric elevators comp hoisting mechanism including a loa d l ifiting platform, a series of landing stations, a main motor and an auxiliary motor each operatively connected to the hoisting mechamsm to o erate the latter at' difierent speeds, manu i means for selectively connecting either of said motors to a source of electrical merg and automatic means for normally causing the deenergization of said auxihary motor whenever theload lifting platform reaches a landing station, said manual means being the sole instrurrientality for permitting the energization of said auxiliary motor.

6. A system of control for electric elevators comprising the combination of a hoisting drum, a main motor operatively connected thereto, an auxiliary motor having an automatically acting releasable mechanical connection with said hoisting drum, electromagnetic means for releasing said connection, a cont-actor electrically controlling said electromagnetic means and provided with an operating coil in series with the main motor circuit, and a manually 0perable device adapted to alternatively connect up the circuits of the main and auxiliar motors, whereby'the' mechanical connection and disconnection of the auxiliary motor is made dependent upon the circuit of the main motor.

7 A system of control for electric elevators comprising the. combination of a hoisting mechanism, a main motors permanently connected therewith, an auxiliary motor, means for normally coupling said auxiliary motor to said hoisting mechanism, electromagnetic means controlled by the main motor circuit for releasing the con-- pling while the circuit of-the main motor is closed, a manually operable device adapted to alternatively connect up the circuits of the main and auxiliary motors, said coupling being adapted to mechanically connect the. auxiliary motor with the hoisting -mechanism whenever the circuit of the main motor is open independently of the electrical connections of the auxiliary motor.

8. A system of control for electric elevators comprising. the combination of hoisting mechanism, a main motor vpermanently connected therewith, an auxiliary motor having a detachable mechanical connection with the hoisting mechanism, means controlled,v by the main motor'circuit for mechanically disconnecting the auxiliary motor from said hoisting mechanism while the main motor is in operation, a. manually operable device adapted in either of two positions to connect up the circuit of the aux-.

member, a series of landing stations along a the path of said load lifting member,

roe-goes main motor operatively connected to the hoisting mechanism, an auxiliary motor, means "for automatically coupling the auxiliary motor to said hoisting mechanism to operate the latter at reduced speed, electromagnetic means for retracting the coupling when the circuit of the main motor is closed, a contac'tor having a controlling coil in series with the main motor and adapted to close an energizing circuit of the electromagnetic means when the contactor oil is energized, a manually operable switch for alternatively connecting up the circuits or" the main and auxiliary motors and automatic means subject to manual control, for opening the circuit of the auxiliary motor whenever said load lifting member reaches one of said landing stations.

10. system of control for electric elevators comprising the combination of a hoisting mechanism, a main motor operatively connected thereto, an auxiliary motor, means for automatically coupling the auxiliary motor to said hoisting mechanism to 01 crate the latte reduced speed, electromagnetic means for retracting coupling when the circuit of the main motor is closed, contactor having a controlling coil in ser es with the main motor to close an energizing circuit of electromagnetic means when the contactor coil is energized, and a manually operable switch for alternatively connecting up the circuits of the main and auxiliary motors, said manually operable switch being adjustable to a n utral position with both motor circuits open and the auxiliary motor coupled to the hoisting mechanism.

ll. A system of control for electric elevators comprising the combination of a reciprocatory carrier, main and auxiliary motors having connections adapted to transmit motion to the load carrier ditl'erent speeds, an independently acting mechanical brake having an electrically op rated brake releasing device provided with an exciting coil in series with both motors, means for automatically releasing the motion transmitting connections of the auxiliary motor from the load carrier when the main motor is energized, and a manually operable switch adapted in one position to connect up a circuit of the main motor, in another position to connect up a circuit of the auxiliary motor, and in third position to disconnect both motors and-release said mechanical brake for operation in maintaining the position of the load carrier.

12. system of control for electric elevators comprising the combination of a reciprocatory load carrier, a main motor having a hoisting drum mounted upon its shalt, an auxiliary motor having associated reduction gears, an automatically acting clutch "for operating the shaft and drum at reduced speed, electrically operated clutch releasing devices controlled by the circuit of the main motor, and a manually operable switch adapted to alternatively close and open the circuits or" the respective motors and also adapted in one position of adjustment to open the circuits of both motors and simultaneusly release said clutch to connect the auxiliary motor with the shaft and drum.

13. A system of control for electric elevators comprising the combination 01"" a re ciprocatory load carrier, a main motor having a hoisting drum mounted upon its shaft, an auxiliary motor having associated reduction gears, an automat1- cally acting clutch for operating the shaft and drum at reduced speed, electrically operated clutch releasing devices controlled by the circuit of the main motor, a manually operable switch adapted to alternatively close and open the circuits oi the respective motors and also adapted in one position of adjustment to open the circuits of both motors and simultaneously release said clutch to connect the auxiliary motor with the shaft and drum, and means dependent upon the position of the load carrier for automatically opening the circuit of the auxiliary motor when the manuall operable switch is in one position of ac,- justment, whereby the auxiliary motor may be rendered automatically inoperable when tie load carrier reaches certain predetermined positions, the main motor being subject to continuous manual control in all positions of the load-carrier.

l t. A. system of control for electric elevators comprising an elevator platform, means for reciprocating the platform, a main motor permanentlyconnected thereto, an auxiliary motor, means for detachably connecting said auxiliary motor to said reciprocating mechanism, a manually operable device tor connecting either or said motors to a source of electric energy independently ot the other motor, said device having a neutral position with the circuits of both motors open, means for automatically breaking a circuit of the aimiliary motor when the elevator platform is in a certain predetermined position, means for adjusting the manually operable device to connect up a circuit of the auxiliary motor independent of said automatic circuit breaking means, while allowing the circuit of the main motor to be closed with the platform in such position, whereby said platform may, at the will of the operator, be actuated continuously by the main motor or to' a predetermined stopping position by the auxiliary motor.

15. A system of control for electric elevators comprising the combination with an elevator platform and an operatively associated hoisting drum, "of a main motor permanently connected with the hoisting drum, an auxiliary motor adapted to be detachably connected with the hoisting drum, a circuit breaker adapted to automatically open a circuit of the auxiliary motor when the platform is in predetermined positions of elevation, and a manually operable de vice adapted to alternatively connect up the main and auxiliary motors with a source of electrical energy, said device being adapted in one position to close a circuit of the auxiliary motor subject to the action of said circuit breaker and in another position to close an independent circuit of said auxiliary motor. v

16. A system of control for electric elevators comprising the combination with an elevator platform and associated hoisting mechanism, of a set of main and auxiliary motors for operating said platform, electrically controlled means for mechanically disconnecting the auxiliary motor from the hoisting mechanism when the main motor is in operation, a circuit breaker for the auxiliary motor adapted for automatic operhoisting mechanism, of main and auxiliary motors adapted to alternatively actuate said hoisting mechanism, a manually operable switch adapted in either of two positions to connect up a circuit of the auxiliary motor and in a third position to connect up a circuit of the main motor, and a circuit breaker adapted to automatically open one of the auxiliary motor circuits at predetermined stages in the operation of the hoisting mechanism, whereby said switch may be utilized to operateboth of the motors independently of said circuit breaker orto operate said auxiliary motor subject to the action of said circuit breaker;

' PETER H. BRODESSER. 

